The present disclosure is generally directed to surgical apparatuses, systems, and methods and, more particularly, pneumatically powered surgical cutting and fastening instruments. The surgical apparatuses, systems, and methods may have application in conventional endoscopic and open surgical instrumentation as well as application in robotic-assisted surgery.
Surgical cutting and fastening instruments (staplers) have been used in the prior art to simultaneously make a longitudinal incision in tissue and apply lines of staples on opposing sides of the incision. Such instruments commonly include a pair of cooperating jaw members that, if the instrument is intended for endoscopic or laparoscopic applications, are capable of passing through a cannula passageway. One of the jaw members receives a staple cartridge having at least two laterally spaced rows of staples. The other jaw member defines an anvil having staple-forming pockets aligned with the rows of staples in the cartridge. The instrument includes a plurality of reciprocating wedges which, when driven distally, pass through openings in the staple cartridge and engage drivers supporting the staples to effect the firing of the staples toward the anvil.
Over the years, a variety of different methods for actuating the cutting and staple deployment components have been developed. For example, U.S. Pat. No. 6,978,921 to Shelton, IV et al. discloses a surgical stapling instrument that employs tissue severing and staple deployment components that are driven through manual actuation of various trigger mechanisms on the handle. Other surgical stapling apparatuses have been developed that employ battery powered motors. Such a device is disclosed in U.S. Pat. No. 5,954,259 to Viola et al.
Still other surgical staplers are actuated by a source of pressurized gas. For example, U.S. Pat. No. 6,619,529 to Green et al. discloses a surgical stapler that employs a source of pressurized gas in the handle that is used to power a cylinder that is also located within the handle. The cylinder houses a piston assembly that is actuated by admission of the pressurized gas into the cylinder. The piston is configured to coact with components located in the elongated tube portion and handle member to cause the deployment of the staples and the surgical knife in the distally mounted end effector. Such design, however, employs a complex collection of components for transmitting the motion of the handle-mounted piston to the components located in the end effector portion of the device. In addition, when using such a device, there is a risk that the power source becomes depleted during the surgical procedure because there is no way of monitoring the amount of gas remaining in the gas cartridge. If this occurs during the firing or retraction cycles, such devices lack means for easily exchanging the spent container with a new container or auxiliary power source.
Another pneumatically powered surgical stapling device is disclosed in US Patent Publication No. US 2006/0151567 to Roy. This device employs a pneumatically powered motor or piston system supported in the handle of the device for creating a motion that is employed to actuate the end effector. This device may be powered by removable cartridges or from an external power source, such as the hospital's existing pneumatic air or gas supply.
Such pneumatically powered devices that employ cartridges or containers in the handle portion of the device are also hampered by the size of the gas cylinder required to store the pressurized gas at sufficient volumes to facilitate actuation of the device a desired number of times at a minimum usable pressure. In the past, devices designed for large numbers of applications/procedures would either require a large cylinder to be used or, if smaller cylinders were used, such cylinders would have undesirably high pressures. In addition, devices that employ removable cartridges that can be used an unlimited number of times must be reprocessed and resterilized. Such arrangements can dramatically change performance capabilities and may therefore be less desirable.
Other problems exist with prior pneumatically powered surgical apparatuses. For example, once the surgeon activates the instrument through a single switch or activation trigger, the instrument progresses through or at least attempts to complete the firing cycle. Thereafter, the firing components may be retracted by the drive system. Prior pneumatically actuated instruments also lack suitable electrical control mechanisms to control the actuated pneumatic components. Prior pneumatically actuated surgical apparatuses also lack suitable electrical recording capabilities to provide information associated with the pneumatically actuated surgical apparatus to the surgeon.
Consequently there is a need for a pneumatically powered and electrically controlled surgical stapling device that does not require the use of an extensive collection of components to transfer the pneumatically generated stapling and firing motions to the end effector components.
There is a need for a pneumatically powered instrument with electrical control mechanisms. Conventional pneumatically powered instruments employ pressurized gas to actuate cutting and/or stapling functions. Once the pneumatic cylinder is actuated, however, it is difficult to control the flow rate of the gas from the pneumatic cylinder or the pressurization of the pneumatic system. Thus, there is a need to integrate pneumatic actuators with one or more electrical control elements to control the rate of release of the pressurized gas from the pneumatic cylinder and thus control the pressurization of the pneumatic system. It also would be advantageous to employ the electrical control elements to control the release of the gas from the pneumatic cylinder at a variable rate.
There is another need for a pneumatically powered instrument with electrical recording capabilities. One reason for employing electrical recording capabilities is for the clinician to be able to verify via an endoscope that the desired location for the cut has been achieved, including a sufficient amount of tissue has been captured between opposing jaws. Otherwise, opposing jaws may be drawn too close together, especially pinching at their distal ends, and thus not effectively forming closed staples in the severed tissue. At the other extreme, an excessive amount of clamped tissue may cause binding and an incomplete firing. When endoscopic surgical instruments fail, they are often returned to the manufacturer, or other entity, for analysis of the failure. If the failure resulted in a critical class of defect in the instrument, it is necessary for the manufacturer to determine the cause of the failure and determine whether a design change is required. In that case, the manufacturer may spend many hundreds of man-hours analyzing a failed instrument and attempting to reconstruct the conditions under which it failed based only on the damage to the instrument. It can be expensive and very challenging to analyze instrument failures in this way. Also, many of these analyses simply conclude that the failure was due to improper use of the instrument. Thus, there is a need for a pneumatically powered instrument that employs a number of sensors and electrical recording elements to selectively discharge the activation of the pneumatic cylinder and/or to selectively pressurize the pneumatic system and record any condition of the instrument based on readings from the sensors.
There is a further need for a pneumatically powered instrument with electrical feedback capabilities. Once the instrument closes upon tissue before firing, electrical feedback enables the clinician to verify via an endoscope that the desired location for the cut has been achieved, including a sufficient amount of tissue has been captured between opposing jaws.
Otherwise, opposing jaws may be drawn too close together, especially pinching at their distal ends, and thus not effectively forming closed staples in the severed tissue. At the other extreme, an excessive amount of clamped tissue may cause binding and an incomplete firing.
Endoscopic staplers/cutters continue to increase in complexity and function with each generation. One of the main reasons for this is the quest for lower force-to-fire (FTF) to a level that all or a great majority of surgeons can handle. Surgeons typically prefer to experience proportionate force distribution to that being experienced by the end-effector in the forming the staple to assure them that the cutting/stapling cycle is complete, with the upper limit within the capabilities of most surgeons (usually around 15-30 lbs). They also typically want to maintain control of deploying the staple and being able to stop at anytime if the forces felt in the handle of the device feel too great or for some other clinical reason. These user-feedback effects are not suitably realizable in present pneumatically powered instruments. As a result, there is a general lack of acceptance by physicians of pneumatically powered instruments where the cutting/stapling operation is actuated by merely pressing a button.
With current surgical instruments, the status of the instrument is generally not provided to a user (clinician) of the surgical instrument during a procedure. For example, with current mechanical endocutters, the presence of the staple cartridge, the position of the knife, the time elapsed since clamping, and the magnitude of the firing force are generally not provided to the user. Without visual and/or audible feedback, each user must rely on his or her own “feel” to determine the status of the surgical instrument, thereby creating inefficiencies, inconsistencies, and potential damage to the surgical instrument.